Flexible sheet securing device for printing rollers



May 15, 1956 e. R. BRODIE 2,745,344

FLEXIBLE SHEET SECURING DEVICE FOR PRINTING ROLLERS Filed March 2, 1955 3 Sheets-Sheet 1 INVENTOR. GEORGE R. BRODlE G. R. BRODIE 2,745,344

FLEXIBLE SHEET SECURING DEVICE FOR PRINTING ROLLERS May 15, 1956 3 Sheets-Sheet 2 Filed March 2, 1955 1'3 21 [III m w I mw @N 6 WW 24 V 9T I 2 89 WR w I- 28 INHI- FIG. 6

y 1956 G. R. BRODIE 2,745,344

FLEXIBLE SHEET SECURING DEVICE FOR PRINTING ROLLERS Filed March 2, 1955 3 Sheets-Sheet 3 INVENTOR. GEORGE R. BRODIE FLEXIBLE SIEET SECURING DEVICE FOR PRINT W G RBLLERS George Rogers Brodie, Lower Merion Township, Montgomery County, Pa., assignor to Fredk. H. Levey Company, Inc., New York, N. Y.

Application March 2, 1955, Serial No. 491,720

7 Claims. (11. 101-41s.1

periphery of the plate cylinder and each end of the plate firmly held in position thereon by a clamping device, known as 'a plate lock-up.

Stats Patent The invention provides improved lock-up means for adjusting and clamping the plates in position on the plate cylinder.

In multi-color printing, for instance, it is essential that each plate be precisely positioned on the plate cylinder in order to obtain exact register of each plate on the web. Frequently, it is found that the image is not quite accurately positioned on the plate, and it then becomes necessary to twist or cant the plate slightly with respect to the plate cylinder in order to bring the printed image into precise register with that of the other plates.

It is also important that the plate fit snugly and be securely held in position about the plate cylinder, in order to prevent any buckling of the plate. Further it is highly desirable that the width of the lock-up be as small as practicable, since high quality printing has not been obtained over that portion of the periphery of the cylinder occupied by the clamping device, and it is, of course, desired to minimize the non-printing area of the plate.

It has heretofore been customary to weld the respective ends :of the printing plate to clamp bars extending the width of the plate and which are adapted to fit into a slot in the periphery of the plate cylinder parallel to its axis. These slots have been provided with movable clamping jaws of considerable width extending along each side thereof, adapted to clamp the bars in position, and operated by means of screws extending through the periphery of the cylinder along each side of the slot. Access to these screws has been through holes cut through the plate adjacent its respective ends. This arrangement has necessitated the leaving of a gap of considerable width between the ends of the plate and a further non-printing area of considerable width extending along each side of the gap.

One marked advantage, obtained in accordance with the present invention, is that the width of the gap between the edgesof the plate is materially reduced. A further advantage is that the necessity of welding the ends of the plate to clamp bars is entirely avoided. A still further advantage is that it is no longer necessary to provide openings through the plate to give access to the adjustment screws operating the jaws. The non-printing area of the plate is thereby reduced to a minimum.

Other advantages of my improved plate lock-up will appear from the following description thereof, with reference to the accompanying drawings which represent a particularly advantageous embodiment of the invention, and of which- 2,745,344 Patented May 15, 1956 'ice Fig. 5 is a longitudinal vertical sectional view along the line 5-5 of Fig. 3,

Fig. 6 is a fragmentary end view of the plate cylinder along the line 66 of Fig. 2, partly broken away to show a transverse section of the lock-up along the line 66' of Fig. 5,

Fig. 7 is a longitudinal horizontal sectional view along the line 7-7 of Fig. 8 showing a middle quarter of the lock-u Fig. 8 is a longitudinal vertical sectional view along the line 8-8 of Fig. 4,

Fig. 9 is a longitudinal horizontal sectional view along the line 9-9 of Fig. 8, and

Fig. 10 is an enlarged fragmentary view of the clamping arrangement of Fig. 3.

The two end-quarters of the lock-up device are similar.

Likewise, the two middle-quarters are similar. Therefore, it is only necessary to describe in detail one endquarter and one middle-quarter of the lock-up. It will be understood that the drawings are not necessarily to precise scale.

In the drawings the plate cylinder is fragmentarily represented at 1 and the printing plate thereon is indicated at 2. The plate cylinder is rotatably supported at each end by shaft 3. A slot is milled into the periphery of the cylinder, parallel to its axis and extending the entire width of the cylinder to be covered by the printing plate, to receive the'lock-up device, which is also coextensive with the width of the printing plate to be secured thereby to the cylinder.

The lock-up device consists essentially of cooperating clamping jaws 4 and the cooperating. clamping member 5, each of which extends over the entire length of the lockup, and means presently to be described for operating and adjusting the clamping jaws. The clamping jaws 4 and clamping member 5 are of uniform configuration throughout their length and are adapted tobe moved sideways with respect to other members of the lock-up device. Means are provided at intervals along their length for effecting such movement.

The plate to be' secured to the periphery of the plate cylinder need not be permanently fastened in any way to the clamping jaws 4, nor to the clamping member 5.

However, before. applying the plate to the cylinder, its ends are bent, substantially as shown at 6 in Fig. 10 of the drawings to facilitate the securing of the ends.

In applying the plate, the jaws 4 are loosened, by means presently to be described, so as to permit the insertion of the respective bent ends of the plate between the jaws and the lug, or upward extension of the clamping member 5, and into the respective groove 7 extending along the base at each side of the lug 8. After the ends of the plates have been so inserted, the clamping jaws 4 are moved together, by means presently to be described, so as to clamp the plate ends between the lug 8 and the lower portion of the respective jaws 4.

The clamping jaws 4 are tapered at their outer ends, thereby reducing to a minimum the peripheral surface of the plate cylinder occupied thereby. These jaws are with advantage so proportioned that they may be seprespective racks and pinions;

' 'arately inserted into the slot provided therefor through th'e'slofbetw'een the stationary face plates {wanna-x: tend along each side of the jaws, flush with the periphery of the plate cylinder, and are cut down at each endvso that they fit under and are secured to the lock-up assembly' at each end, beyond'the' side edges of the plate, V by means of a p'latei0u and-machineiscrews 711,1 a's m'ore clearly shown 'in-Fig. fi of the drawings;

The lower portions: of the-facezplates ares cut'away' at;inte rvals along; their" lengtlrto' receive'pushen bars :12,

- positioned at intervals 2 at each side 1 of the. clamping: jaws and-provided; withi shoulders 13- adapted to bear against the jaws at point intermediate the height of'the jawsz.

V 'I h'eseipilsher ba'rs 'IZEare"adaptedflo beiforced against 7 the respective jaws by means of 'eccentrically mounted in Fig: 4'of"'flie drawings at30; for receiving socliet lie'adi cards: 14? forniedn by: extensionsnf: the, supporting, shafts 7 of pinions'15.

The? shaftsl oft pinions' are. rotatably; mounted at each-fend inzbearings's-lb'gland; are. adapted -toi betrotated 'by, meahsbfk one of thei parallel; racks: 17, which: extend through 'theinterior of the lock up parallel to the axis;of2 the plate;cylinder.1 a

t'I'hesrespective racks. 17: are? in. turn ada' ted Ito: be'

7 moved longitudinally by means of socket-head capscrews,I

foriinstancei'ofi the Alle'n 2 carpi-screw type; 18, whiclr are threaded into the ends of the respective racks 17-. As moreiclearly shoWrrainzl-"rigs'; l5 andKS: of; the drawings,

. bearer rings 19 are shrunken onto each end of-thegsliaft 3 and close" the: respective endsl ofi the; longitudinal? slot 1 containing the racks. Advantageonsly; the: inner p'ora tiomtofzfthe bearer: rings: isiconstructed'rofi softi steeli to'i'fai cilitatezboringaand an outertprimary'bearer ring219a of! hardenedasteel zis shrunken ontotheinnerring' so sas to minimizeiwearz The :bearer'ringi19;is recessed and drilled :7 atillho receive theisocket1cap screws -18and thegscrewsi:

' are held against longitudinal movement by means 'of-end' plate1215secured to -the oute'r faceof bearer ring 19iby' means of socket head screws 22; Access to thei'socket heads-iof iscrews 18 is through op'ening's: 23 extending throughthezendlplatell';= 1 i V The; number and spacing of' the pusherIbars is subject tta'considerable' variation; In the partici llar lockup de+ a The member 26 is also drilled at intervals, ass

screws 31 which are threaded into the face plates 9. as indicated at 32, thus securing the face plates to the member 26. The clamping member 5 is likewise drilled at H intervals to coincide with the screw holes 27 to provide access to those screws, through the slot between the face 1 plates 9, prior to the'insertion of the clamping jaws 4; 7

Gear teeth may be providedon only those portions of a the racks'adjacent the pinions, As shown in Fig-2 ,.,the t racksare'recessed', as indicated at 33; adjacentnorf-coacting pinions.

The lock-up may, be: assembled as: follows; prior to; insertion'in the receiving: slot; of the plate-cylinder: The F clamping member 5 is first placed in'the groove prov ided V holes 27 of -member 26, the lock+up assembly is now ready" :for insertion in the longitudinal groove 'ofthe plate 1 cylinder, and is secured in position by means of; said; screwsgaccess to-whichcan be'hadlthroughthe groove between the face plates? and the holes extendingthrough the clamping member 5. Thereafter, the clamp in gija'vvsa V 4-may beseparately. inserted through the-'slot betweemthe 7 by; means of plates 10 andscrew'slli' Screws;18: are:g' 35,

vice; shown imthe drawingstherezare 28 pusher b'arsim j 311;; 1 4 being-spaced at equal intervals along? cach side of the-clamping jaws. Accordingly,ithereare 28 pinions and? 28S racksifor" actuating the respective pusher bars.

' Thrzl'd pusherfbai-s in oh'e' halfofithe cylinder"are actuate'dtbyz racks which are: inqturngactnated by cap-screws positioned at thatfend 'of the cyli ndfe'ri Thie thre'ei'pairs 7 f pusherzbarsanea'rest the' 'end of thelcylinder are; can

trolled? bythe screwsappearing in: two vertical: rows ofithree each in Fig- 6 of the;:drawing and the next; four:

pairs iofimshetj bars arecontrollechby the eight' cap-ser'ews appearingiin that two, outer rows 1 of four screws each The racks for controllingthefirst'three pairs of pusher ba'rsi'extend; only! about rine fourth of the length of the lojckmpz and stop blocksfl t gsecu'red to the frameofthe lockaupfv byfime'ans: of socket head" s'crewsz 25 are pro'-* 1 vided;.-the; racks for controlling-the'zniext four pairs of pusher: bars will: tern'linatesoniewhat short of the"- middle 7 of thetlocleup: so I as not: to interfere with 'ra'cks' f'or con- 7 r trolling-the pusher bars ofithe;next:quartei of the lock up.

A QparticIflarlyJ desirable: aspect ofithis' invention is theeaswwith: which the: lock up' canbe assembled and se assemblyie more clearly shown" by- Figs: 3 an'd 4 0E the cured fin position in the plate cylinder; The method of face plates;

7 The -respectivetends: of the face plates are: then secured;

thensinserted and threaded into. the respectivetracks and:

In securing; the: printing plate' -to thei plate' cylinder;

the ends ofrthe: plate are first bent, as, shown iniFiga 1'0, V and insertedbetween the clamping"jawsas Pl'VlOUSl-Yvdflf scribed. Theiends ofthe plate are thenclamped in thatr position" by forcing the pusher bars against the sides of by turning the respective adjustment 7 the: clamping" jaws, screws 18.:

The: outer: bend at: the

resp'ect totthe clamping-jaws; as lock-up forces rare-exe'rted; and the plate is held snugly against: thezcircum fer'enceiof' the cylinder-at the point where the plate isbent to en'ter the lock up. .Thus any rising or 'bulging oftlie' plate at these 'bent'points, which rnight'r'esult in a bump on either side of the gap, is positively 'avoide'di Affair" flier Pl h v n us? placed in position; a

' they are-adjusted and tightened about'th rcylind.er,.landi V canted-thereon ifnecessa'ry, by appropriat backing-mg, a 0 p essing forward'of the appropriate pusherba'rs be r:

7 ing at intervals against opposite sides of the clamping jaw During such canting operation, as-previbuslynotfifl the drawings. The mainbo'dy of thedock-upds'the member 7 2" 6 which1ex'tends over the" entire length of the lock up':

membert2 6 is cut" away; to-a greater or'less extent; as indicated in the drawings; to rovide space far the; Attintervalauie member" Z6isals'o drilled, as indiEat'edZaLZ'i, for receiving socket- Head'screws 28, whichw are threaded as indicated'at-ZQ into the body of. the plate cylinder to secure thev lockup.

thereto. V j

ends'iof the plate remain :se'cu rely'held between'the lower ends of the respectivejaws and the clamping member S' the jaws.

B y reason of the fact cylinder which theyoccupy aremot distinguishableywith respect to printing quality, from the other peripheral surface ofthe cylinder; 7 Further: thefplate is readilrbe'nt flatattheouter endsofthe'jaws, thus minimizingirregular ities albng the sides of the gap betweentheniu Occupying 7 only a very small peripheral-area of the cylinder, thefnon the-end plates 21 are then; s'ecured'to theaendsof? theta plate-cylindertby-means bfcapscrews ZZ.

extreme ends. of: the" plate arei- -preferablyreinforc'ed by a: double thickness of thesheet as=shown-in Eigl 1O. These'bend's project intothe grooves at thebaseof lug8 and' jare 'securelyheld therein by thereispectiv e jawsd By -this means both ends. ofthe plat'e 7 are positivelysecured against slipping outwardly, with; =7 i' so"as*to"avoidf slippage'between the ends of the plateand 7 that the face plates:9 are=fiusli 7 the surface" of tlieplatecylinder and aresecurely held in position" at all times; the peripheral surfaces Offlit? and clamping member 5 may be moved side-ways with respect to the groove between the face plates and by shifting these clamping members in one direction at one end of the cylinder and in the other direction at the other end of the cylinder, a maximum or any intermediate amount of canting of the printing plate can be obtained.

The extent to which the clamping members may be moved sideways will depend, of course, upon the amount of clearance provided and also the eccentricity of the cams 14. An eccentricity of about 3 with a corresponding clearance, is usually sufficient in most conditions encountered.

One advantage of my improved lock-up is that the plate, when being clamped on the cylinder, is pulled from both ends, thus making it possible to tighten a stainless steel plate, for instance, around the cylinder. A further advantage is that the pull across the width of the plate is variable and is exerted at numerous points. Thus, if the bend in the plate is not straight, or if the plate is somewhat bulged, the plate can nevertheless be pulled up snugly on the cylinder by appropriately varying the pull at the various sections along the end of the plate. It is particularly advantageous that the clamping jaws 4 be long and willowy, so that they can be caused to conform to the outer bends in the plate instead of forcing the bend in the plate to conform to the clamping jaws as the plate is being tightened.

While I have described intdetail a particularly advantageous embodiment of the invention, it will beunderstood that the invention, in its broader aspect, is not restricted to the precise arrangement shown, but that various modifications and equivalents will be suggested by my disclosure and may be employed within the scope of the invention.

For instance, equivalent means may be employed for forcing the pusher bars against the clamping jaws and for actuating those means. Also the invention, in its broader aspect, is not restricted to the particular arrangement shown for assembling the lock-up and for securing the lock-up in the plate cylinder.

I claim:

1. A lock-up for clamping a printing plate to a plate cylinder of a rotary printing press, comprising a pair of cooperating clamping jaws co-extensive with the width of the printing plate, having upper edges tapering toward each other and terminating substantially flush with the peripheral surface of the cylinder, a lug positioned between the lower ends of the clamping jaws and adapted to cooperate therewith in clamping the respective ends of the plate, pusher bars positioned at intervals along each side of the pair of clamping jaws and adapted to bear thereon at a point intermediate the height of the jaws, means associated with each pusher bar adapted to force the pusher bar and the associated clamping jaw toward the cooperating jaw and means actuated from one end of the lock-up, and extending longitudinally through the cylinder for actuating the pusher bar forcing means.

2. A lock-up for clamping a printing plate to a plate cylinder of a rotary printing press comprising a pair of parallel face plates adapted to fit flush with the peripheral surface of the cylinder, co-extensive with the width of the printing plate and spaced apart to provide a gap for the insertion of the respective ends of the plate, a pair of cooperating clamping jaws co-extensive with the length of the face plates having upper edges tapering toward each'other extending through the gap and terminating in relatively thin edges substantially flush with the'face plates, a lug positioned between the lower ends of the clamping jaws and adapted to ocooperate therewith in clamping the respective ends of the plate, pusher bars positioned at intervals along each side of the pair of clamping jaws, and adapted to bear thereon at points intermediate the height of the jaws, means associated with each pusher bar adapted to force the bar and the associated clamping jaw toward the cooperating jaw and means actuated from one end of the lock-up and extending longitudinally through the cylinder for actuating the pusher bar forcing means.

3. A lock-up for clamping a printing plate to a plate cylinder of a rotary printing press comprising a pair of parallel face plates adapted to fit flush with the peripheral surface of the cylinder, co-extensive with the width of the printing plate and spaced apart to provide a gap for the insertion of the respective ends of the plate, a pair of cooperating clamping jaws co-extensive with the length of the face plates, having upper edges tapering toward each other extending through the gap and terminating in relatively thin edges substantially flush with the face plates, a lug positioned between the lower ends of the clamping jaws and adapted to cooperate therewith in clamping the respective ends of the plate, pusher bars positioned at intervals along each side of the pair of clamping jaws, and adapted to bear thereon at points intermediate the height of the jaws, a cam associated with each pusher bar and adapted to force the pusher bar and the associated clamping jaw toward the cooperating jaw, and means actuated from one end of the lock-up for actuating the respective cams.

4. A lock-up for clamping a printing plate to a plate cylinder of a rotary printing press comprising a pair of parallel face plates adapted to fit flush with the peripheral surface of the cylinder, coextensive with the width of the printing plate and spaced apart to provide a gap for the insertion of the respective ends of the plate, a pair of cooperating clamping jaws co-extensive with the length of the face plates, having upper edges tapering toward each other extending through the gap and terminating in relatively thin edges substantially flush with the face plates, a lug positioned between the lower ends of the clamping jaws and adapted to cooperate therewith in clamping the respective ends of the plate, pusher bars positioned at intervals along each side of the pair of clamping jaws, and adapted to bear thereon at points intermediate the height of the jaws, a cam associated with each pusher bar and adapted to force the pusher bar and the associated clamping jaw toward the cooperating jaw, a pinion gear associated with each cam and adapted to actuate said cam, a rack cooperating with each pinion, extending longitudinally of the lock-up, and means extending through an end of the cylinder for actuating the respective racks.

5. A lock-up for clamping a printing plate to a plate cylinder of a rotary printing press comprising a pair of parallel face plates adapted to fit flush with the peripheral surface of the cylinder, co-extensive with the width of the printing plate and spaced apart to provide a gap for the insertion of the respective ends of the plate, a pair of cooperating clamping jaws co-extensive with the length of the face plates, having upper edges tapering toward each other extending through the gap and terminating in relatively thin edges substantially flush with the face plates, a lug positioned between the lower ends of the clamping jaws and adapted to cooperate therewith in clamping the respective ends of the plate, pusher bars positioned at intervals along each side of the pair of clamping jaws and adapted to bear thereon at points intermediate the height of the jaws, a cam associated with each pusher bar and adapted to force the pusher bar and the associated clamping jaw toward the cooperating jaw, 

